#include<iostream>
using namespace std;
class Complex{
	public:
		Complex(double r=0.0,double i=0.0){
			real=r;
			imag=i;
		}
		double real;
		double imag;
};
Complex operator-(const Complex&a,const Complex&b){
	return Complex(a.real+b.real,a.imag+b.imag);
}
int main()
{
	Complex a(1,2),b(2,3),c;
	c=a-b;
	cout<<c.real<<","<<c.imag<<endl;
	return 0;
}